He said Miliband should go even further and ban "zero hours contracts".

Employment lawyer at City law firm Charles Russell, Syma Spanjers has told HR magazine she thinks it will be "difficult for any party to eradicate" the contracts completely.

"In practice Labour may struggle to enforce the proposed ban on zero hour contracts given the popularity of casual arrangements in some sectors such as retail, cleaning and catering," Spanjers said.

She added: "As well as benefits for employers, many employees enjoy the flexibility of zero hour contracts if they cannot commit to a fixed number of hours per week, perhaps due to family commitments or because they are studying or retired but keen to have occasional work."

Workers on these contracts are on call to work but can be given no hours, as a result, no pay.

Spanjers said in these "uncertain economic times" zero hour contracts can be an "attractive option for employers" requiring a flexible workforce in order to quickly respond to variable business needs.

She said: "Being able to access a 'bank' of available workers during short-term busy periods takes away the pressure and associated costs of recruiting permanent staff, only to have to consider letting them go when workload diminishes."

Burnham also suggested incentives to encourage firms to pay the living wage rather than just the minimum wage to workers, such as lower business rates or tax relief.

The living wage currently stands at £8.55 in London and £7.45 elsewhere in the UK, compared to the National Minimum Wage of £6.19.

He said the party was "beginning now to set out our stall" for the 2015 campaign.